@kreansanm, I think the answer to this is, "it depends". You can see what email address is associated with the Roku account by going to Settings->System->About. There is no phone number associated with a Roku account and I don't believe Roku ever sends text messages (but scammers do). However, different channels/apps use different methods to authenticate. You can subscribe to some service using an email address that's different than the one associated with the Roku account. In general, if you're being asked to authenticate or sign-in to something it's because you've established (or it's asking you to establish) an account directly with the provider. It's really not any different than signing into something on a web browser. If prompted for an email address to sign in you will/should be given the choice of using the email address that's associated with the Roku device or entering a different one. If you use the wrong one I could see how you'll never receive any response.
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